In a modern commercial aircraft, a flight crew makes flight plan entries and modifications through a Flight Management System (FMS). The FMS receives inputs related to the desired destination, and the FMS builds a flight plan based on the inputs. Referring to FIG. 1, an offset 100 is a modification to a flight plan 102 in which a parallel flight path is constructed at a given offset distance 103 either to the left or the right of the flight plan 102. Offsets 100 are primarily used by aircraft 126 to avoid terrain obstacles or weather 104. In the example shown in FIG. 1, the flight plan 102 includes five legs 106, 108, 110, 112, and 114 that connect five waypoints 116, 118, 120, 122, and 124. The offset 100 begins at a present position (PPOS) 128 and includes a capture path 130, a parallel path 132, and a return path 134. The capture path 130 extends from the flight plan 102 to the full offset distance 103. The parallel path 132 tracks the flight plan 102 at the full offset distance 103. The return path 134 extends from the parallel path 132 back to the flight plan 102. The offset 100 has a capture angle 136 and a return angle 138 of 45° with respect to the flight plan 102. The capture angle 136 and return angle 138 are fixed at 45°. This can result in an inefficient offset and/or an offset that is subject to little or no pilot modification. Moreover, the capture path 130 and return path 134 must occur within the bounds of a single leg, only include a single segment at the fixed capture and return angles 136 and 138, and are unable to traverse multiple legs, large course changes, and non-intersecting legs.
Accordingly, it is desirable to provide methods and systems for constructing offsets from flight plans that minimize deviation from original flight plan and increases the efficiency of the offset. Moreover, it is desirable to provide methods and systems for constructing offsets from flight plans that enable pilot modifications, including variable capture and return angles. Additionally, it is desirable to provide systems and methods for constructing offsets from flight plans that traverse multiple legs, non-intersecting legs, and large course changes. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.